If you believe the anti-Birtwistle lobby, a recording of The Mask of Orpheus should show it up for the musically empty thing it is. Strip away the dense, often perplexingly multi-layerd stage activity and the mystique is gone, the score is revealed as meaningless sound and fury. I confess: even as one of those who was blown away by ENO's 1986 stage premiere, I had my doubts. Could the music hold the attention without the action?

The answer is yes. In fact, I was surprised at how quickly each of the three substantial acts seemed to run its course. Even the purely electronic dances (accompanying the miniature "Passing Cloud" and "Allegorical Flower" ballet sequences) didn't stretch patience too far.

Act 2 - Orpheus' ultimately futile descent into Nightmare/ Hades to rescue Euridice - is more or less musically self-sufficient, an immense elemental crescendo followed by desolation and catastrophe (Orpheus' suicide). But Acts 1 and 3 are full of remarkable things: the tortured birth of music, speech and poetry at the beginning; the sacrifice of Orpheus (another version of the myth!) before the end; and the strange, primal dreamscape of the final pages - electronic sounds that vaguely recall but entirely transcend moody New Ageism.

In such a huge cast of singers and players, it's hard to pick out individuals for praise. But Jon Garrison as Orpheus The Man (as opposed to Orpheus The Myth) sings, yells, gabbles and stammers magnificently. Marie Angel's appropriately titled "First Hysterical Aria" as the Oracle of the Dead pierces and fixes itself in the memory.

Contributions from the BBC Singers and the winds, brass and percussion of the BBC Symphony Orchestra are predictably strong and conductor Andrew Davis (with assistant Martyn Brabbins) holds it together as if he knows it intimately. Recording and presentation are excellent too, though be prepared to do some serious homework on the text before sitting down to follow it with the music.